Pimentelia Laboissière, 1939

Bolz, Helmut & Wagner, Thomas, 2014, Revision of the Afrotropical Pimentelia Laboissière, 1939 (Coleoptera, Chrysomelidae, Galerucinae), Zootaxa 3881 (1), pp. 49-62 : 50-52

Pimentelia Laboissière, 1939

Type species: Pimentelia kuanduensis Laboissière, 1939: 118 –119. By original designation.

Description. Total length of adult specimens 5.85–10.90 mm; mean of total length for distinct species ranges between 7.56 and 9.38 mm. Females are somewhat larger than males. Larvae and pupae are unknown.

Head. Labrum, frons and vertex are reddish- or yellowish-brown or dark brown, sometimes black. Maxillary and labial palpi mostly brown or black throughout. Basal antennomeres mostly yellow, sometimes also brown or black, apical antennomeres darker towards apex and brown or black. Antennomeres broad and thick from fourth to last antennomere, second and third antennomere delicate, significantly shorter and smaller than following antennomeres, antenna usually reaching end of metasternum ( Figs 7 , 12 ). Second antennomere usually more than half as long than third antennomere, length of second to third antennomere 0.56–0.82, range of means 0.59–0.73. Fourth antennomere significantly longer than third ( Figs 9 , 14 ), length of third to fourth antennomere 0.45–0.63, range of means 0.52–0.54. Eyes convex and slightly ovate ( Figs 7 , 12 ), ratio width of eye to interocular distance (WE/ DE, Fig. 1 ) 0.36–0.43, range of means 0.39–0.41. Slight transverse depression between the posterior part of eyes.

Thorax. Coloring basically yellow, yellowish-brown, rarely brown or black, in one species with an oily or satin sheen. Pronotum yellow, brownish-yellow, reddish-brown or totally brown or black. Prothoracic coxal cavities closed behind ( Fig. 3 ). Pronotal width 2.15–3.50 mm, range of means of pronotal width 2.77–3.05 mm; pronotal length 1.10–2.10 mm, range of means of pronotal length 1.45–1.83 mm; ratio pronotal length to width (PL/PW, Fig. 1 ) 0.47–0.60 range of means of pronotal length to width 0.52–0.60. Elytron blackish-, yellowish- or reddishbrown, or entirely yellow or black; sometimes black or blackish-brown with irregular yellow spots or brownishyellow with black irregular spots at humerus and apical third; sometimes elytra slightly iridescent because of microsculpturation; characters vary, even within species. Elytra with deep and coarse punctuation. Elytral length 4.60–8.00 mm, range of means 5.71–7.03 mm; elytral width 3.00– 5.20 mm, range of means 3.97–4.15 mm. Ratio maximum width of both elytra to length of elytron (EW/EL, Fig. 1 ) 0.56–0.79, range of means 0.59–0.69. Scutellum triangular, yellow, reddish-yellow, brown or black, colouring often differing from elytron, often varying within species. Colouring of meso- and metathorax ranging from yellowish-brown to brown and black. Legs usually entirely brownish-yellow, yellowish-brown, brown or black, sometimes becoming darker from coxa towards tarsus and intraspecifically variable. Metatarsus moderately elongate ( Fig. 6 ), length of basi-metatarsus to length of metatibia 0.30–0.41; range of means of different species basi-metatarsus to metatibia 0.30–0.34.

Abdomen. Five visible sternites (ventrites). Usually reddish- or yellowish-brown or brownish-yellow in colour. Seventh sternite (fifth ventrite) in male with two incisions ( Fig. 5 a), absent in female ( Fig. 5 b).

Male genitalia. Bilaterally symmetrical, parallel-sided from base towards apex, slender and conical ( Fig. 13 ); deeply incised apically, median lobe usually long and slender. Tectum very short and hardly distinguishable. Tegmen positioned in apical third of median lobe, long and Y-shaped. Basal orifice usually ovate to rectangular; parameres are absent. Endophallus lacking strongly sclerotised spiculae ( Fig. 13 ). Apical section of the sclerotized ductus ejaculatorius not protruding; endophallic brush covered by tectum.

Female genitalia. Spermatheca with barrel- or pear-shaped nodulus ( Fig. 8 ), which leads to a curved and strongly angled cornu. This configuration is very similar for all species.

Diagnosis. Pimentelia species are Galerucinae with only moderately elongate basi-metatarsi ( Fig. 6 c). The paired elytra are not dorso-ventrally compressed as in Galerudolphia but usually widened in the middle or in the apical third and bulging like in Candezea or Neobarombiella. Dorsal coloration varies from uniformly yellow to brown, reddish-brown or dark-brown to black. Pimentelia maculata has black spots on the yellow elytron or yellow spots on black elytron, while this pattern can occur intraspecifically along uniformly colored specimens ( Figs 12 a–e). The underside is usually brownish-yellow to brown, or black. The legs are mostly brownish- or reddishyellow or brown or black. The basal antennomeres are usually paler than those towards the apex, brownish-yellow with the apical antennomeres usually brown or black, but sometimes intraspecifically also brown throughout. The second antennomere is at least more than half to nearly two-thirds as long as the third antennomere (length of second to third antennomere 0.56–0.82) ( Figs 9 , 14 ), intraspecific means range between 0.59 and 0.73. In Candezea the second antennomere is half as long as the third (length of second to third antennomere 0.52–0.58) in Monolepta the second and third antennomere are about the same length (0.83–1.10); in Neobarombiella the second antennomere is at least half as long as the third antennomere, on average two-thirds of the length of the third antennomere in most species, but rarely of the same length (length of second to third antennomere 0.50–1.00), intraspecific means range between 0.51 and 0.93. The third antennomere is slightly less to more than half as long as the fourth antennomere, intraspecific length of third to fourth antennomere 0.45–0.63, range of means for different species 0.53–0.54; on average the fourth antennomere is slightly shorter in female than in male specimen, length of third to fourth antennomere 0.45–0.56 (mean: 0.52) in male specimen of P. maculata , 0.52–0.63 (mean: 0.57) in female specimens ( Figs 9 , 14 ). In Neobarombiella and Candezea no such clearly defined sexual dimorphism of the antennomeres can be found. In Monolepta the third antennomere is always less than half as long as the fourth (0.36–0.46), in other genera the third antennomere is at least half as long as the fourth antennomere ( Bonesioides 0.50–0.81; Barombiella 0.60–0.78; Galerudolphia 0.60–0.78 and Candezea 0.62–0.64). Beside this sexual dimorphism one of the most important characters of Pimentelia are the apically significantly widened antennomeres, which are more delicate in species of Candezea or Neobarombiella.

The pronotum of Pimentelia is characteristically strongly trapezoidal as in Neobarombiella, Bonesioides , Galerudolphia , and Barombiella , but differs from Candezea , Afrocrania , Afrocandezea and Monolepta , where the pronotum generally has a rectangular shape. In Pimentelia the pronotum is relatively long like in Neobarombiella, Candeza or Galerudolphia (range of means for different species of pronotal length to width 0.52–0.60 in Pimentelia , 0.42–0.59 in Candezea , 0.51–0.62 in Galerudolphia and 0.44–0.56 in Neobarombiella). In Barombiella violacea the posterior pronotal angles are distinctly pointed, the pronotum is on average broader, pronotal length to width 0.39–0.49. The prothoracic coxal cavities are closed in Pimentelia ( Fig. 3 ) while they are wide open in some species of Bonesioides . In Pimentelia the elytra usually become wider in the middle or the apical third, and they are also strongly convex as in Monolepta, Neobarombiella or Candezea . Bonesioides and Galerudolphia specimens are dorso-ventrally flattened and on average have more slender elytra. The maximum width of both elytra to length of the elytron is 0.56–0.79 in Pimentelia , 0.55–0.82 in Neobarombiella and 0.39–0.77 in Galerudolphia .

The median lobe of Pimentelia shows rather similar characteristics like the median lobe in Neobarombiella, specifically in the apical section ( Figs 13 ). It is usually slender, parallel-sided, and tube-like with a more or less deep apical incision. Median lobes with apical incisions occur also in all species of Bonesioides and in Barombiella violacea (Jacoby, 1894) . Species of the first genus have basally parallel-sided, short and broad median lobes with narrowed and conical apex. The endophallic armature comprises distinct spiculae (cf. Freund & Wagner 2003, Wagner & Freund 2003). The endophallus in Pimentelia is small and without distinct spiculae. This characteristic is very different from all species of Monolepta , Candezea , Afrocrania and Afrocandezea , which all have median lobes with no apical incision and large, characteristic and group specific, endophallic spiculae.

In summary, Galerucinae from Continental Africa with short second and third antennomere where the second antennomere is nearly two-thirds as long as the third or nearly equally long, a strongly trapezoidal pronotum without dorsal depressions, broad and convex elytron without rounded convexities and with significant elytral punctuation, closed procoxal cavities, moderately elongate basi-metatarsi, and a slender, parallel-sided, tube-like median lobe with a more or less deep apical incision and endophallus without small delicate spiculae, belong to Pimentelia

Distribution. Pimentelia maculata is distributed in South Africa and Zimbabwe. The distribution of P. kuanduensis seems to be restricted to Angola, but this could be because there are only three specimens available ( Fig. 11 ).

Figures

FIGURE 1. Dorsal view illustrating the morphometric measurements taken for external characters: TL—total length; EL—elytral length; EW—maximum width of both elytral combined; PL—pronotal length; PW—pronotal width; WE—maximal width of eye; DE—minimal interocular distance; 2., 3., 4. — length of second, third and fourth antennomere; TA—length of first tarsomere of metatarsus; TI—length of metatibia.

FIGURES 6. Pimentelia maculata (Jacoby, 1885). Legs: a—prothoracic leg, b—mesothoracic leg, c—metathoracic leg (scale bar = 1 mm).

FIGURE 11. Distribution of Pimentelia species.

FIGURES 7 – 9. Pimentelia kuanduensis Laboissière, 1939. FIGURE 7. Dorsal view with colour pattern of some specimens; FIGURE 8. Spermatheca; FIGURE 9. Antennomeres 1 – 4 of two different females (a, b) (scale bars = 1 mm).

FIGURES 12 – 14. Pimentelia maculata (Jacoby, 1885). FIGURES 12 a-e. Dorsal view with colour pattern of some specimens; FIGURES 13. Aedeagus, a—lateral, b—ventral, c—dorsal; FIGURES 14. Antennomeres 1 – 4 of two different males (a, b) and two different females (c, d) (scale bars = 1 mm).

FIGURES 2 – 5. Pimentelia maculata (Jacoby, 1885), ventral view of: FIGURE 2. Head; FIGURE 3. Pronotum; FIGURE 4. Meso- and metathorax; FIGURE 5. Abdomen: 5 a—male, 5 b—female (scale bar = 1 mm).